1. Technical Field
The present invention relates to a semiconductor memory apparatus and a method of testing the same. In particular, the present invention relates to a semiconductor memory apparatus having a noise generating block that provides a noise environment equivalent to a normal mode even in a test mode, and a method of testing the same.
2. Related Art
In general, the quality of semiconductor memory apparatus is determined through a test operation. The test operation is generally performed in a compress test mode. In contrast to a normal mode in which data input/output operations of the memory banks are separately performed, the compress test mode is a test mode in which a data input/output test is performed on a plurality of memory banks at the same time in order to improve time efficiency in the data input/output test of the semiconductor memory apparatuses.
However, in the semiconductor memory, the amount of input/output data in the normal mode may be different from the amount of input/output data in the test mode. Correspondingly, the amount of noise in the compress test mode may be different from the amount of noise in the normal mode. Furthermore, conditions, such as the operating frequency of a clock and the like, can be different between a wafer test step that generally uses the compress test mode and a test step after a packaging process that generally uses the normal mode. Therefore, a difference in the amount of noise between the test mode and the normal mode is generated.
As such, in case amount of noise generated in the wafer test step of the semiconductor memory apparatuses is different from the amount of noise generated in the test step after the packaging process, the percentage of defects increases due to the difference in test conditions when the semiconductor memory apparatuses are manufactured.